Philly’s coronavirus curves: Daily updated stats on COVID-19 – Billy Penn


Mark Henninger / Imagic Digital

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Philly passed its pandemic peak in April, but the coronavirus that causes COVID-19 is still very much alive and circulating in the city and region.

Safety restrictions on business activity continue to take an economic toll across almost all sectors and industries, but government officials maintain they’re necessary. “The virus is still here, and maybe growing here in Philadelphia,” Health Commissioner Dr. Tom Farley said on July 21, “and we’re going to have to learn how to live with it and how to manage it.”

Since there’s no indication of when an effective vaccine might be introduced, the best we can hope for right now is to avoid another surge — which is unfortunately happening in several other areas on the country.

What exactly is the situation in Philly?

The city’s Department of Public Health publishes a wealth of data online each day. Many of the charts and graphs are useful, especially in viewing the racial and ethnic disparities — you can see how COVID-19 is disproportionately affecting the Black community — but others are less obvious.

To help make it easier to understand coronavirus trends in Philadelphia, we’re presenting two visualizations.

These charts will automatically refresh on a daily basis, so bookmark this page and check back whenever you want an update. Tip: If you’re viewing on mobile, turn your phone sideways to see the full set of data.

(If you’re viewing on mobile, turn your phone sideways to see the full set of data.)

This chart shows three numbers in proportion to one another.

The purple line shows case count, i.e. how many Philadelphians tested positive for SARS-CoV-2. The blue line show hospitalizations — how many patients checked in with coronavirus symptoms. The red line is fatalities, showing how many people died of COVID-related illness.

Reporting of this data can lag, thanks to holdups in any number of steps along the way.

There are delays in reporting results by national outfits like LabCorp and Quest, which are trying to work through a backlog from elsewhere in the nation (they process about a quarter of Philly’s tests, according to Health Commissioner Farley). There can also be delays in the reported number of deaths, since not all people are diagnosed similarly and Philadelphians may be treated outside the city. Health department staff regularly does a match with various state databases to find new Philly fatalities.

Because of those and other issues, the above graph uses a rolling seven-day average, not a daily-reported number, for each data point.

(If you’re viewing on mobile, turn your phone sideways to see the full set of data.)

Two different stats are shown on this chart. The green bars are total number of tests given each day, and the blue line is the percentage of tests that return positive.

The evolving relationship between these two stats makes for a useful comparison in assessing the state of the pandemic in Philly.

When COVID first arrived in the region, there were only a few test sites available and supplies were limited, so access was restricted to frontline workers and older people experiencing symptoms. Gradually capacity and supply increased, and testing was opened up to anyone who wanted it.

Those trends explain why the early part of graph above looks the way it does: back then, only a few people were getting tested, many of them had extreme symptoms. The more recent part of the graph shows that increased testing does not automatically mean an increase of cases (despite what some politicians have claimed).

Notable: Philly’s positivity rate appears to have plateaued — it’s not getting worse, but it’s also not dropping closer to zero.

Also key to remember: every person can help with the fight to keep the virus at bay.

Wearing masks (over nose and mouth) has been shown to greatly mitigate spread; they’re currently required whenever outside and less than 6 feet from people not in your unit. Also generally maintain distance from others whenever possible, and avoid large gatherings, especially those indoors or where people are loudly singing or shouting.

Want some more? Explore other Philly’s coronavirus response stories.

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